public class Computer {
    public void USBDevice(USB usb){

        usb.ShowCondition();
        usb.OpenDevice();
        usb.CloseDevice();
    }
//如何只执行其中一个功能呢？？？
    public static void main(String[] args) {
        Computer computer = new Computer();

//        Mouth mouth = new USB();
        USB MouthsUSB = new Mouth();
        computer.USBDevice(MouthsUSB);
//        KeyBoard keyBoard = new KeyBoard();
//        USB keyBoardsUSB = new KeyBoard();
//        computer.USBDevice(keyBoard);
//        keyBoard.CloseDevice();
//        keyBoardsUSB.ShowCondition();
    }
}
